drivers/mtd/maps/physmap-core.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Normal mappings of chips in physical memory
   4  *
   5  * Copyright (C) 2003 MontaVista Software Inc.
   6  * Author: Jun Sun, jsun@mvista.com or jsun@junsun.net
   7  *
   8  * 031022 - [jsun] add run-time configure and partition setup
   9  *
  10  * Device tree support:
  11  *    Copyright (C) 2006 MontaVista Software Inc.
  12  *    Author: Vitaly Wool <vwool@ru.mvista.com>
  13  *
  14  *    Revised to handle newer style flash binding by:
  15  *    Copyright (C) 2007 David Gibson, IBM Corporation.
  16  *
  17  * GPIO address extension:
  18  *    Handle the case where a flash device is mostly addressed using physical
  19  *    line and supplemented by GPIOs.  This way you can hook up say a 8MiB flash
  20  *    to a 2MiB memory range and use the GPIOs to select a particular range.
  21  *
  22  *    Copyright © 2000 Nicolas Pitre <nico@cam.org>
  23  *    Copyright © 2005-2009 Analog Devices Inc.
  24  */
  25
  26 #include <linux/module.h>
  27 #include <linux/types.h>
  28 #include <linux/kernel.h>
  29 #include <linux/init.h>
  30 #include <linux/slab.h>
  31 #include <linux/device.h>
  32 #include <linux/platform_device.h>
  33 #include <linux/mtd/mtd.h>
  34 #include <linux/mtd/map.h>
  35 #include <linux/mtd/partitions.h>
  36 #include <linux/mtd/physmap.h>
  37 #include <linux/mtd/concat.h>
  38 #include <linux/mtd/cfi_endian.h>
  39 #include <linux/io.h>
  40 #include <linux/of_device.h>
  41 #include <linux/pm_runtime.h>
  42 #include <linux/gpio/consumer.h>
  43
  44 #include "physmap-bt1-rom.h"
  45 #include "physmap-gemini.h"
  46 #include "physmap-ixp4xx.h"
  47 #include "physmap-versatile.h"
  48
  49 struct physmap_flash_info {
  50         unsigned int            nmaps;
  51         struct mtd_info         **mtds;
  52         struct mtd_info         *cmtd;
  53         struct map_info         *maps;
  54         spinlock_t              vpp_lock;
  55         int                     vpp_refcnt;
  56         const char              *probe_type;
  57         const char * const      *part_types;
  58         unsigned int            nparts;
  59         const struct mtd_partition *parts;
  60         struct gpio_descs       *gpios;
  61         unsigned int            gpio_values;
  62         unsigned int            win_order;
  63 };
  64
  65 static int physmap_flash_remove(struct platform_device *dev)
  66 {
  67         struct physmap_flash_info *info;
  68         struct physmap_flash_data *physmap_data;
  69         int i;
  70
  71         info = platform_get_drvdata(dev);
  72
  73         if (info->cmtd) {
  74                 WARN_ON(mtd_device_unregister(info->cmtd));
  75
  76                 if (info->cmtd != info->mtds[0])
  77                         mtd_concat_destroy(info->cmtd);
  78         }
  79
  80         for (i = 0; i < info->nmaps; i++) {
  81                 if (info->mtds[i])
  82                         map_destroy(info->mtds[i]);
  83         }
  84
  85         physmap_data = dev_get_platdata(&dev->dev);
  86         if (physmap_data && physmap_data->exit)
  87                 physmap_data->exit(dev);
  88
  89         pm_runtime_put(&dev->dev);
  90         pm_runtime_disable(&dev->dev);
  91         return 0;
  92 }
  93
  94 static void physmap_set_vpp(struct map_info *map, int state)
  95 {
  96         struct platform_device *pdev;
  97         struct physmap_flash_data *physmap_data;
  98         struct physmap_flash_info *info;
  99         unsigned long flags;
 100
 101         pdev = (struct platform_device *)map->map_priv_1;
 102         physmap_data = dev_get_platdata(&pdev->dev);
 103
 104         if (!physmap_data->set_vpp)
 105                 return;
 106
 107         info = platform_get_drvdata(pdev);
 108
 109         spin_lock_irqsave(&info->vpp_lock, flags);
 110         if (state) {
 111                 if (++info->vpp_refcnt == 1)    /* first nested 'on' */
 112                         physmap_data->set_vpp(pdev, 1);
 113         } else {
 114                 if (--info->vpp_refcnt == 0)    /* last nested 'off' */
 115                         physmap_data->set_vpp(pdev, 0);
 116         }
 117         spin_unlock_irqrestore(&info->vpp_lock, flags);
 118 }
 119
 120 #if IS_ENABLED(CONFIG_MTD_PHYSMAP_GPIO_ADDR)
 121 static void physmap_set_addr_gpios(struct physmap_flash_info *info,
 122                                    unsigned long ofs)
 123 {
 124         unsigned int i;
 125
 126         ofs >>= info->win_order;
 127         if (info->gpio_values == ofs)
 128                 return;
 129
 130         for (i = 0; i < info->gpios->ndescs; i++) {
 131                 if ((BIT(i) & ofs) == (BIT(i) & info->gpio_values))
 132                         continue;
 133
 134                 gpiod_set_value(info->gpios->desc[i], !!(BIT(i) & ofs));
 135         }
 136
 137         info->gpio_values = ofs;
 138 }
 139
 140 #define win_mask(order)         (BIT(order) - 1)
 141
 142 static map_word physmap_addr_gpios_read(struct map_info *map,
 143                                         unsigned long ofs)
 144 {
 145         struct platform_device *pdev;
 146         struct physmap_flash_info *info;
 147         map_word mw;
 148         u16 word;
 149
 150         pdev = (struct platform_device *)map->map_priv_1;
 151         info = platform_get_drvdata(pdev);
 152         physmap_set_addr_gpios(info, ofs);
 153
 154         word = readw(map->virt + (ofs & win_mask(info->win_order)));
 155         mw.x[0] = word;
 156         return mw;
 157 }
 158
 159 static void physmap_addr_gpios_copy_from(struct map_info *map, void *buf,
 160                                          unsigned long ofs, ssize_t len)
 161 {
 162         struct platform_device *pdev;
 163         struct physmap_flash_info *info;
 164
 165         pdev = (struct platform_device *)map->map_priv_1;
 166         info = platform_get_drvdata(pdev);
 167
 168         while (len) {
 169                 unsigned int winofs = ofs & win_mask(info->win_order);
 170                 unsigned int chunklen = min_t(unsigned int, len,
 171                                               BIT(info->win_order) - winofs);
 172
 173                 physmap_set_addr_gpios(info, ofs);
 174                 memcpy_fromio(buf, map->virt + winofs, chunklen);
 175                 len -= chunklen;
 176                 buf += chunklen;
 177                 ofs += chunklen;
 178         }
 179 }
 180
 181 static void physmap_addr_gpios_write(struct map_info *map, map_word mw,
 182                                      unsigned long ofs)
 183 {
 184         struct platform_device *pdev;
 185         struct physmap_flash_info *info;
 186         u16 word;
 187
 188         pdev = (struct platform_device *)map->map_priv_1;
 189         info = platform_get_drvdata(pdev);
 190         physmap_set_addr_gpios(info, ofs);
 191
 192         word = mw.x[0];
 193         writew(word, map->virt + (ofs & win_mask(info->win_order)));
 194 }
 195
 196 static void physmap_addr_gpios_copy_to(struct map_info *map, unsigned long ofs,
 197                                        const void *buf, ssize_t len)
 198 {
 199         struct platform_device *pdev;
 200         struct physmap_flash_info *info;
 201
 202         pdev = (struct platform_device *)map->map_priv_1;
 203         info = platform_get_drvdata(pdev);
 204
 205         while (len) {
 206                 unsigned int winofs = ofs & win_mask(info->win_order);
 207                 unsigned int chunklen = min_t(unsigned int, len,
 208                                               BIT(info->win_order) - winofs);
 209
 210                 physmap_set_addr_gpios(info, ofs);
 211                 memcpy_toio(map->virt + winofs, buf, chunklen);
 212                 len -= chunklen;
 213                 buf += chunklen;
 214                 ofs += chunklen;
 215         }
 216 }
 217
 218 static int physmap_addr_gpios_map_init(struct map_info *map)
 219 {
 220         map->phys = NO_XIP;
 221         map->read = physmap_addr_gpios_read;
 222         map->copy_from = physmap_addr_gpios_copy_from;
 223         map->write = physmap_addr_gpios_write;
 224         map->copy_to = physmap_addr_gpios_copy_to;
 225
 226         return 0;
 227 }
 228 #else
 229 static int physmap_addr_gpios_map_init(struct map_info *map)
 230 {
 231         return -ENOTSUPP;
 232 }
 233 #endif
 234
 235 #if IS_ENABLED(CONFIG_MTD_PHYSMAP_OF)
 236 static const struct of_device_id of_flash_match[] = {
 237         {
 238                 .compatible = "cfi-flash",
 239                 .data = "cfi_probe",
 240         },
 241         {
 242                 /*
 243                  * FIXME: JEDEC chips can't be safely and reliably
 244                  * probed, although the mtd code gets it right in
 245                  * practice most of the time.  We should use the
 246                  * vendor and device ids specified by the binding to
 247                  * bypass the heuristic probe code, but the mtd layer
 248                  * provides, at present, no interface for doing so
 249                  * :(.
 250                  */
 251                 .compatible = "jedec-flash",
 252                 .data = "jedec_probe",
 253         },
 254         {
 255                 .compatible = "mtd-ram",
 256                 .data = "map_ram",
 257         },
 258         {
 259                 .compatible = "mtd-rom",
 260                 .data = "map_rom",
 261         },
 262         {
 263                 .type = "rom",
 264                 .compatible = "direct-mapped"
 265         },
 266         { /* sentinel */ },
 267 };
 268 MODULE_DEVICE_TABLE(of, of_flash_match);
 269
 270 static const char * const of_default_part_probes[] = {
 271         "cmdlinepart", "RedBoot", "ofpart", "ofoldpart", NULL
 272 };
 273
 274 static const char * const *of_get_part_probes(struct platform_device *dev)
 275 {
 276         struct device_node *dp = dev->dev.of_node;
 277         const char **res;
 278         int count;
 279
 280         count = of_property_count_strings(dp, "linux,part-probe");
 281         if (count < 0)
 282                 return of_default_part_probes;
 283
 284         res = devm_kcalloc(&dev->dev, count + 1, sizeof(*res), GFP_KERNEL);
 285         if (!res)
 286                 return NULL;
 287
 288         count = of_property_read_string_array(dp, "linux,part-probe", res,
 289                                               count);
 290         if (count < 0)
 291                 return NULL;
 292
 293         return res;
 294 }
 295
 296 static const char *of_select_probe_type(struct platform_device *dev)
 297 {
 298         struct device_node *dp = dev->dev.of_node;
 299         const struct of_device_id *match;
 300         const char *probe_type;
 301
 302         match = of_match_device(of_flash_match, &dev->dev);
 303         if (!match)
 304                 return NULL;
 305
 306         probe_type = match->data;
 307         if (probe_type)
 308                 return probe_type;
 309
 310         dev_warn(&dev->dev,
 311                  "Device tree uses obsolete \"direct-mapped\" flash binding\n");
 312
 313         of_property_read_string(dp, "probe-type", &probe_type);
 314         if (!probe_type)
 315                 return NULL;
 316
 317         if (!strcmp(probe_type, "CFI")) {
 318                 probe_type = "cfi_probe";
 319         } else if (!strcmp(probe_type, "JEDEC")) {
 320                 probe_type = "jedec_probe";
 321         } else if (!strcmp(probe_type, "ROM")) {
 322                 probe_type = "map_rom";
 323         } else {
 324                 dev_warn(&dev->dev,
 325                          "obsolete_probe: don't know probe type '%s', mapping as rom\n",
 326                          probe_type);
 327                 probe_type = "map_rom";
 328         }
 329
 330         return probe_type;
 331 }
 332
 333 static int physmap_flash_of_init(struct platform_device *dev)
 334 {
 335         struct physmap_flash_info *info = platform_get_drvdata(dev);
 336         struct device_node *dp = dev->dev.of_node;
 337         const char *mtd_name = NULL;
 338         int err, swap = 0;
 339         bool map_indirect;
 340         unsigned int i;
 341         u32 bankwidth;
 342
 343         if (!dp)
 344                 return -EINVAL;
 345
 346         info->probe_type = of_select_probe_type(dev);
 347
 348         info->part_types = of_get_part_probes(dev);
 349         if (!info->part_types)
 350                 return -ENOMEM;
 351
 352         of_property_read_string(dp, "linux,mtd-name", &mtd_name);
 353
 354         map_indirect = of_property_read_bool(dp, "no-unaligned-direct-access");
 355
 356         err = of_property_read_u32(dp, "bank-width", &bankwidth);
 357         if (err) {
 358                 dev_err(&dev->dev, "Can't get bank width from device tree\n");
 359                 return err;
 360         }
 361
 362         if (of_property_read_bool(dp, "big-endian"))
 363                 swap = CFI_BIG_ENDIAN;
 364         else if (of_property_read_bool(dp, "little-endian"))
 365                 swap = CFI_LITTLE_ENDIAN;
 366
 367         for (i = 0; i < info->nmaps; i++) {
 368                 info->maps[i].name = mtd_name;
 369                 info->maps[i].swap = swap;
 370                 info->maps[i].bankwidth = bankwidth;
 371                 info->maps[i].device_node = dp;
 372
 373                 err = of_flash_probe_bt1_rom(dev, dp, &info->maps[i]);
 374                 if (err)
 375                         return err;
 376
 377                 err = of_flash_probe_gemini(dev, dp, &info->maps[i]);
 378                 if (err)
 379                         return err;
 380
 381                 err = of_flash_probe_ixp4xx(dev, dp, &info->maps[i]);
 382                 if (err)
 383                         return err;
 384
 385                 err = of_flash_probe_versatile(dev, dp, &info->maps[i]);
 386                 if (err)
 387                         return err;
 388
 389                 /*
 390                  * On some platforms (e.g. MPC5200) a direct 1:1 mapping
 391                  * may cause problems with JFFS2 usage, as the local bus (LPB)
 392                  * doesn't support unaligned accesses as implemented in the
 393                  * JFFS2 code via memcpy(). By setting NO_XIP, the
 394                  * flash will not be exposed directly to the MTD users
 395                  * (e.g. JFFS2) any more.
 396                  */
 397                 if (map_indirect)
 398                         info->maps[i].phys = NO_XIP;
 399         }
 400
 401         return 0;
 402 }
 403 #else /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
 404 #define of_flash_match NULL
 405
 406 static int physmap_flash_of_init(struct platform_device *dev)
 407 {
 408         return -ENOTSUPP;
 409 }
 410 #endif /* IS_ENABLED(CONFIG_MTD_PHYSMAP_OF) */
 411
 412 static const char * const rom_probe_types[] = {
 413         "cfi_probe", "jedec_probe", "qinfo_probe", "map_rom",
 414 };
 415
 416 static const char * const part_probe_types[] = {
 417         "cmdlinepart", "RedBoot", "afs", NULL
 418 };
 419
 420 static int physmap_flash_pdata_init(struct platform_device *dev)
 421 {
 422         struct physmap_flash_info *info = platform_get_drvdata(dev);
 423         struct physmap_flash_data *physmap_data;
 424         unsigned int i;
 425         int err;
 426
 427         physmap_data = dev_get_platdata(&dev->dev);
 428         if (!physmap_data)
 429                 return -EINVAL;
 430
 431         info->probe_type = physmap_data->probe_type;
 432         info->part_types = physmap_data->part_probe_types ? : part_probe_types;
 433         info->parts = physmap_data->parts;
 434         info->nparts = physmap_data->nr_parts;
 435
 436         if (physmap_data->init) {
 437                 err = physmap_data->init(dev);
 438                 if (err)
 439                         return err;
 440         }
 441
 442         for (i = 0; i < info->nmaps; i++) {
 443                 info->maps[i].bankwidth = physmap_data->width;
 444                 info->maps[i].pfow_base = physmap_data->pfow_base;
 445                 info->maps[i].set_vpp = physmap_set_vpp;
 446         }
 447
 448         return 0;
 449 }
 450
 451 static int physmap_flash_probe(struct platform_device *dev)
 452 {
 453         struct physmap_flash_info *info;
 454         int err = 0;
 455         int i;
 456
 457         if (!dev->dev.of_node && !dev_get_platdata(&dev->dev))
 458                 return -EINVAL;
 459
 460         info = devm_kzalloc(&dev->dev, sizeof(*info), GFP_KERNEL);
 461         if (!info)
 462                 return -ENOMEM;
 463
 464         while (platform_get_resource(dev, IORESOURCE_MEM, info->nmaps))
 465                 info->nmaps++;
 466
 467         if (!info->nmaps)
 468                 return -ENODEV;
 469
 470         info->maps = devm_kzalloc(&dev->dev,
 471                                   sizeof(*info->maps) * info->nmaps,
 472                                   GFP_KERNEL);
 473         if (!info->maps)
 474                 return -ENOMEM;
 475
 476         info->mtds = devm_kzalloc(&dev->dev,
 477                                   sizeof(*info->mtds) * info->nmaps,
 478                                   GFP_KERNEL);
 479         if (!info->mtds)
 480                 return -ENOMEM;
 481
 482         platform_set_drvdata(dev, info);
 483
 484         info->gpios = devm_gpiod_get_array_optional(&dev->dev, "addr",
 485                                                     GPIOD_OUT_LOW);
 486         if (IS_ERR(info->gpios))
 487                 return PTR_ERR(info->gpios);
 488
 489         if (info->gpios && info->nmaps > 1) {
 490                 dev_err(&dev->dev, "addr-gpios only supported for nmaps == 1\n");
 491                 return -EINVAL;
 492         }
 493
 494         pm_runtime_enable(&dev->dev);
 495         pm_runtime_get_sync(&dev->dev);
 496
 497         if (dev->dev.of_node)
 498                 err = physmap_flash_of_init(dev);
 499         else
 500                 err = physmap_flash_pdata_init(dev);
 501
 502         if (err) {
 503                 pm_runtime_put(&dev->dev);
 504                 pm_runtime_disable(&dev->dev);
 505                 return err;
 506         }
 507
 508         for (i = 0; i < info->nmaps; i++) {
 509                 struct resource *res;
 510
 511                 info->maps[i].virt = devm_platform_get_and_ioremap_resource(dev, i, &res);
 512                 if (IS_ERR(info->maps[i].virt)) {
 513                         err = PTR_ERR(info->maps[i].virt);
 514                         goto err_out;
 515                 }
 516
 517                 dev_notice(&dev->dev, "physmap platform flash device: %pR\n",
 518                            res);
 519
 520                 if (!info->maps[i].name)
 521                         info->maps[i].name = dev_name(&dev->dev);
 522
 523                 if (!info->maps[i].phys)
 524                         info->maps[i].phys = res->start;
 525
 526                 info->win_order = get_bitmask_order(resource_size(res)) - 1;
 527                 info->maps[i].size = BIT(info->win_order +
 528                                          (info->gpios ?
 529                                           info->gpios->ndescs : 0));
 530
 531                 info->maps[i].map_priv_1 = (unsigned long)dev;
 532
 533                 if (info->gpios) {
 534                         err = physmap_addr_gpios_map_init(&info->maps[i]);
 535                         if (err)
 536                                 goto err_out;
 537                 }
 538
 539 #ifdef CONFIG_MTD_COMPLEX_MAPPINGS
 540                 /*
 541                  * Only use the simple_map implementation if map hooks are not
 542                  * implemented. Since map->read() is mandatory checking for its
 543                  * presence is enough.
 544                  */
 545                 if (!info->maps[i].read)
 546                         simple_map_init(&info->maps[i]);
 547 #else
 548                 simple_map_init(&info->maps[i]);
 549 #endif
 550
 551                 if (info->probe_type) {
 552                         info->mtds[i] = do_map_probe(info->probe_type,
 553                                                      &info->maps[i]);
 554                 } else {
 555                         int j;
 556
 557                         for (j = 0; j < ARRAY_SIZE(rom_probe_types); j++) {
 558                                 info->mtds[i] = do_map_probe(rom_probe_types[j],
 559                                                              &info->maps[i]);
 560                                 if (info->mtds[i])
 561                                         break;
 562                         }
 563                 }
 564
 565                 if (!info->mtds[i]) {
 566                         dev_err(&dev->dev, "map_probe failed\n");
 567                         err = -ENXIO;
 568                         goto err_out;
 569                 }
 570                 info->mtds[i]->dev.parent = &dev->dev;
 571         }
 572
 573         if (info->nmaps == 1) {
 574                 info->cmtd = info->mtds[0];
 575         } else {
 576                 /*
 577                  * We detected multiple devices. Concatenate them together.
 578                  */
 579                 info->cmtd = mtd_concat_create(info->mtds, info->nmaps,
 580                                                dev_name(&dev->dev));
 581                 if (!info->cmtd)
 582                         err = -ENXIO;
 583         }
 584         if (err)
 585                 goto err_out;
 586
 587         spin_lock_init(&info->vpp_lock);
 588
 589         mtd_set_of_node(info->cmtd, dev->dev.of_node);
 590         err = mtd_device_parse_register(info->cmtd, info->part_types, NULL,
 591                                         info->parts, info->nparts);
 592         if (err)
 593                 goto err_out;
 594
 595         return 0;
 596
 597 err_out:
 598         physmap_flash_remove(dev);
 599         return err;
 600 }
 601
 602 #ifdef CONFIG_PM
 603 static void physmap_flash_shutdown(struct platform_device *dev)
 604 {
 605         struct physmap_flash_info *info = platform_get_drvdata(dev);
 606         int i;
 607
 608         for (i = 0; i < info->nmaps && info->mtds[i]; i++)
 609                 if (mtd_suspend(info->mtds[i]) == 0)
 610                         mtd_resume(info->mtds[i]);
 611 }
 612 #else
 613 #define physmap_flash_shutdown NULL
 614 #endif
 615
 616 static struct platform_driver physmap_flash_driver = {
 617         .probe          = physmap_flash_probe,
 618         .remove         = physmap_flash_remove,
 619         .shutdown       = physmap_flash_shutdown,
 620         .driver         = {
 621                 .name   = "physmap-flash",
 622                 .of_match_table = of_flash_match,
 623         },
 624 };
 625
 626 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
 627 static struct physmap_flash_data physmap_flash_data = {
 628         .width          = CONFIG_MTD_PHYSMAP_BANKWIDTH,
 629 };
 630
 631 static struct resource physmap_flash_resource = {
 632         .start          = CONFIG_MTD_PHYSMAP_START,
 633         .end            = CONFIG_MTD_PHYSMAP_START + CONFIG_MTD_PHYSMAP_LEN - 1,
 634         .flags          = IORESOURCE_MEM,
 635 };
 636
 637 static struct platform_device physmap_flash = {
 638         .name           = "physmap-flash",
 639         .id             = 0,
 640         .dev            = {
 641                 .platform_data  = &physmap_flash_data,
 642         },
 643         .num_resources  = 1,
 644         .resource       = &physmap_flash_resource,
 645 };
 646 #endif
 647
 648 static int __init physmap_init(void)
 649 {
 650         int err;
 651
 652         err = platform_driver_register(&physmap_flash_driver);
 653 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
 654         if (err == 0) {
 655                 err = platform_device_register(&physmap_flash);
 656                 if (err)
 657                         platform_driver_unregister(&physmap_flash_driver);
 658         }
 659 #endif
 660
 661         return err;
 662 }
 663
 664 static void __exit physmap_exit(void)
 665 {
 666 #ifdef CONFIG_MTD_PHYSMAP_COMPAT
 667         platform_device_unregister(&physmap_flash);
 668 #endif
 669         platform_driver_unregister(&physmap_flash_driver);
 670 }
 671
 672 module_init(physmap_init);
 673 module_exit(physmap_exit);
 674
 675 MODULE_LICENSE("GPL");
 676 MODULE_AUTHOR("David Woodhouse <dwmw2@infradead.org>");
 677 MODULE_AUTHOR("Vitaly Wool <vwool@ru.mvista.com>");
 678 MODULE_AUTHOR("Mike Frysinger <vapier@gentoo.org>");
 679 MODULE_DESCRIPTION("Generic configurable MTD map driver");
 680
 681 /* legacy platform drivers can't hotplug or coldplg */
 682 #ifndef CONFIG_MTD_PHYSMAP_COMPAT
 683 /* work with hotplug and coldplug */
 684 MODULE_ALIAS("platform:physmap-flash");
 685 #endif